This combo photo showing, top from left to right, ousted Egyptian President Hosni Mubarak, former Libyan leader Moammar Gadhafi, and former Tunisian President Zine El Abidine Ben Ali, bottom from left to right, former Yemen's President Ali Abdullah Saleh, Syrian President Bashar Assad, and ...

FILE - In this Oct. 10, 2010 file photo, Libyan leader Moammar Gadhafi, center, with Egyptian President Hosni Mubarak, right, and his Yemeni counterpart Ali Abdullah Saleh, left, pose during a group picture with Arab and African leaders during the second Afro-Arab summit in Sirte, Libya.

PHOTO: Houthi fighters stand on a truck as they secure a street where pro-Houthi protesters demonstrated to commemorate the fourth anniversary of the uprising that toppled former President Ali Abdullah Saleh in Sanaa, Feb. 11, 2015.

PHOTO: Yemeni army soldiers lifted by anti-government protestors, chants slogans and wave their national flag as they celebrate President Ali Abdullah Saleh's departure to Saudi Arabia, in Sanaa, Yemen, Sunday, June 5, 2011.

PHOTO: Yemeni army officers lifted by anti-government protestors, hold up their rifles while being sprayed with foam as they celebrate President Ali Abdullah Saleh's departure to Saudi Arabia, in Sanaa, Yemen, Sunday, June 5, 2011.